2 X LR44 ThruNite Ti

Here’s something that I’ve wanted to do for awhile now. It’s a brass body to use two LR44 button batteries with my ThruNite Ti head. The head has been locked out to firefly mode only. I’m guessing that it will run for about 50-60 hours on these tiny batteries. I could have made this light even smaller if I had not included the keying attachment or had I made it for one cell.

Wow! That's a great idea...I like it a lot! By firefly only I assume you put tape between the positive pressure contacts (or something to that effect)? Btw, outstanding machine work.

I want to make one now Tongue Out

Normally, you would place a piece of tape between the tab and the high mode contact, but, on this light this is not needed. This particular light was the victim of a rather rigorous torture test (note the general roughness and big dent on the bezel) and the subsequent tear-down of the light to inspect the internals damaged something and now it refuses to enter high mode.

Hehe...I noticed. Just looked like a well loved light to me :) Although now I wonder about why the high mode stopped working if the base pad is getting good contact.... I haven't taken the driver out of mine yet, so I can only sit here and speculate.

I looked at the driver board under magnification and some component right under the high mode contact has broke off. I'll see if I can break out the macro gear and get a picture. There's a second board just above it that prevents me from fixing it with my trusty soldering iron so it may not get repaired.

Here's a picture of the board with the broken solder joint. I figured out how to do macro pictures on the iPhone!

I don't have a fine enough tip on my soldering iron to reach in there and fix it.

I bet you could repair that by heating up the positive tab below the driver and pushing down on the chip when it reflows. Since the heat transfer is going straight through the electrical connection, it shouldn’t cause any undue damage to the surrounding components.

Not sure what those poor little LR44’s would think of high mode though :stuck_out_tongue:

Nicely done!
That is a truly pocket friendly design you’ve come up with. Shame about the high mode though - just for sports I’d love to see those tiny batteries power it up in high :slight_smile:

+1

Thanks, guys. It’s a fun little project. The next plan is to make a replacement bezel for it so that everything matches. As far as running it on high using those little button cells, I’m guessing it’ll be fine for about two hours and will probably only give around 30-ish lumens due to voltage sag. After that, it’ll probably not light up very well.

Oh, yeah, this is what it looked like with the original body.